/*
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package eu.fastl.dragster.web.filter;

import javax.servlet.ServletRequest;

import eu.fastl.dragster.RegisteringBean;

/**
 * Interface used by the Cache Filter to create cache keys for request
 *
 * @author Ernst Fastl
 */
public interface CacheKeyGenerator extends RegisteringBean {

    /**
     * Creates a cache key based on a Servlet Request
     *
     * @param request
     *            the Servlet Request
     * @return the cache key for this request or null if the request should not
     *         be cached
     */
    public Object createKey(ServletRequest request);

}
